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Fastest way to replace NAs in a large data.table
I have a large data.table , with many missing values scattered throughout its ~200k rows and 200 columns. I would like to re code those NA values to zeros as efficiently as possible.
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Get MD5 hash of big files in Python
I have used hashlib (which replaces md5 in Python 2.6/3.0) and it worked fine if I opened a file and put its content in hashlib.md5() function.
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Sort a Custom Class List
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ahsteeleahsteele
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is it possible to select EXISTS directly as a bit?
I was wondering if it's possible to do something like this (which doesn't work):
9 Answers
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Evaluating a mathematical expression in a string
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Pyparsing can be used to parse mathematical expressions. In particular, fourFn.py
shows how to parse basic arithmetic expressions. Below, I've rewrapped fourFn into a numeric parser class for easier reuse.
from __future__ import division...
How to filter (key, value) with ng-repeat in AngularJs?
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Angular filters can only be applied to arrays and not objects, from angular's API -
"Selects a subset of items from array and returns it as a new array."
You have two options here:
1) move $scope.items to an array or -
2) pre-filter the ng-repe...
Is MATLAB OOP slow or am I doing something wrong?
I'm experimenting with MATLAB OOP , as a start I mimicked my C++'s Logger classes and I'm putting all my string helper functions in a String class, thinking it would be great to be able to do things like a + b , a == b , a.find( b ) instead
of strcat( a b ) , strcmp( a, b ) , retrieve first...
JQuery: 'Uncaught TypeError: Illegal invocation' at ajax request - several elements
I have two select elements, A and B: when A's selected option changes, B's options must be updated accordingly. Each element in A implies many elements in B, it's a one-to-many relationship (A contains nations, B should contain cities located in the given nation).
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Is this object-lifetime-extending-closure a C# compiler bug?
I was answering a question about the possibility of closures (legitimately) extending object-lifetimes when I ran into some extremely curious code-gen on the part of the C# compiler (4.0 if that matters).
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Define a lambda expression that raises an Exception
How can I write a lambda expression that's equivalent to:
6 Answers
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